Patients with end-stage renal disease, regardless of etiology, require hemodialysis several times a week as an absolute medical necessity. Furthermore, such dialysis-dependent patients have chronic pulmonary compromise due to ventilation perfusion mismatching. Consequently, end stage renal patients have an increased susceptibility to further pulmonary insults, which may include the accumulated micro-thrombi that can shower the pulmonary microvasculature as micro-emboli during relatively uncontrolled thrombolytic and thrombectomy interventions.
Hemodialysis necessarily, inherently requires a reliable vascular access supplied with a robust blood flow that can support the associated large fluid and blood volume shifts. In order to provide adequate vascular access, an AV fistula is surgically created by anastamosing a peripheral artery and vein, typically in an arm or leg. The turbulent blood flow within an AV fistula creates areas of relative blood stasis which thereby predispose to thrombus formation and clot growth that often further leads to occlusion of the vascular lumen. Clotted AV fistulae are relatively common, and necessitate surgical clot removal, or synonymously, thrombectomy to salvage the AV fistula vascular access; if the clot is too extensive, it becomes necessary to tie off, which is to say, ligate, the clotted AV fistula and create a new one at another anatomic site.
Furthermore, AV fistula thrombectomies are done in an Operating Room since currently available techniques involve either open dissection with arteriotomy access to the clot, or closed techniques with the associated increased risks of uncontrolled hemorrhage, both situations requiring the concentrated resources available in an operating room.
It is a goal of the present invention to provide a medical thrombectomy device that can safely be used outside the operating room, whether in a facility x-ray suite or dialysis unit, in a procedure room or bedside.
It is also a goal of the subject invention to provide for optimal thrombectomy by the combined effects of mechanical agitation and shearing and balloon displacement with peri-thrombus delivery of pharmacologic agents.
It is an important objective of the present invention to minimize the size of the access puncture into the blood vessel in order to insert the thrombectomy devices' nested coaxial catheters.